Randomized, double‐blind, placebo‐controlled trial of interferon Alfa2a with and without amantadine as initial treatment for chronic hepatitis C

Abstract

Although the antiviral effects of amantadine sulphate (1‐aminoadamantan sulphate) have not been characterized for the hepatitis C virus (HCV), previous pilot studies have suggested promising results in patients with chronic hepatitis C. The aim of the present study was to compare the efficacy, safety, and health‐related quality of life (HRQOL) of interferon alfa (IFN‐α) alone or in combination with oral amantadine for treatment of chronic hepatitis C. One hundred nineteen previously untreated patients with chronic hepatitis C were randomly allocated to treatment with IFN‐α2a at a dose of 6 megaunits 3 times a week subcutaneously for 24 weeks, followed by 3 megaunits thrice weekly for an additional 24 weeks plus amantadine sulphate administered orally 100 mg twice a day for 48 weeks or the same IFN regimen plus a matched placebo. The primary endpoint was undectable serum HCV RNA (<1,000 copies/mL) at week 24 after treatment. At the end of treatment and the 24‐week follow‐up period serum HCV RNA was undetectable in 20 (34%) and 6 (10%) of the 59 patients treated with the combination IFN‐α plus amantadine and in 20 (33%) and 13 (22%) of the 60 patients treated with IFN‐α alone, respectively (P = n.s.). Discontinuation of therapy for adverse events was similar in both treatment groups. Although treatment with IFN‐α worsened HRQOL, combination with amantadine showed a substantial trend to improve fatigue and vigor. In conclusion, combination therapy IFN‐α plus amantadine is as effective as IFN‐α monotherapy in previously untreated patients with chronic hepatitis C.